It is well documented that the elderly and post-surgical patients are at a heightened risk of falling. These individuals are often afflicted by gait and balance disorders, weakness, dizziness, confusion, visual impairment, and postural hypotension (i.e., a sudden drop in blood pressure that causes dizziness and fainting), all of which are recognized as potential contributors to a fall. Additionally, cognitive and functional impairment, and sedating and psychoactive medications are also well recognized risk factors. In such instances, it is becoming increasingly common to use electronic means to monitor the afflicted patients, with the intent that a nearby (or remote) caregiver will be alerted by the electronics if the patient seeks to rise to his or her feet.
Generally speaking, electronic patient monitors work by first sensing an initial status of a patient, and then generating a signal when that status changes, e.g., he or she has sat up in bed, left the bed, risen from a chair, etc., any of which situations could pose a potential cause for concern in the case of an at-risk patient. Electronic bed and chair monitors typically use a pressure sensitive switch in combination with a separate electronic monitor which conventionally contains a microprocessor of some sort. In a common arrangement, a patient's weight resting on a pressure sensitive mat (i.e., a “sensing” mat) completes an electrical circuit, thereby signaling the presence of the patient to the microprocessor. When the weight is removed from the pressure sensitive switch, the electrical circuit is interrupted, which fact is similarly sensed by the microprocessor. The software logic that drives the monitor is typically programmed to respond to the now-opened circuit by triggering some sort of alarm—either electronically (e.g., to the nursing station via a conventional nurse call system) or audibly (via a built-in siren) or both. Additionally, many variations of this arrangement are possible and electronic monitoring devices that track changes in other patient variables (e.g., wetness/enuresis, patient activity/inactivity, etc.) are available for some applications.
General information relating to mats and electronic monitors for use in patient monitoring may be found in U.S. Pat. Nos. 4,179,692, 4,295,133, 4,700,180, 5,600,108, 5,633,627, 5,640,145, 5,654,694, and 6,111,509 (the last of which concerns electronic monitors generally). Additional information may be found in U.S. Pat. Nos. 4,484,043, 4,565,910, 5,554,835, and 5,623,760 (sensor patents) and U.S. Pat. No. 5,065,727 (holsters for electronic monitors), the disclosures of all of which patents are all incorporated herein by reference. Further, co-pending U.S. patent application Ser. No. 09/285,956 (discussing a sensing device which contains a validation circuit incorporated therein) and U.S. patent application Ser. No. 09/944,622, (for automatically configured electronic monitor alarm parameters) are similarly incorporated herein by reference.
Those familiar with the patient monitoring arts will recognize that a typical electronic monitor contains a number of control switches on the top or front thereof. As an example, it is customary to provide switches that reset the unit, that increment or decrement various control parameters (e.g., exit delay time, alarm volume, etc.), that place the unit on hold, etc. Needless to say, it is critical that the caregiver be easily able to read and accurately modify and set these and other parameters. However, this can become problematic in the evening, when the floor lights are intentionally lowered to help the patients sleep. In such a case, the attendants who are charged with checking the status of the electronic monitors at night are faced with the prospect of either turning on the room lights in order to read the display (at the risk of disturbing the patient(s) in the room) or utilizing a flashlight or other light source (which is an added expense, is subject to being mislaid, and requires periodic replacement/recharging of its power source).
Additionally, it is preferable that the volume of the exit alarm that is sounded by the electronic monitor be reduced in volume during the evening and early morning hours. This might be done for many reasons but among the more obvious ones are that the overall noise level of the facility is lower during those times so that the alarm does not need to be heard above as much ambient noise. Further, in the evening it is desirable that patients be allowed to sleep if they are disposed to do so and an unnecessarily loud exit alarm can disturb patients that are housed in the same room or located several rooms distant from the source of the alarm.
However, as desirable as is might be to lower the alarm volume at night it is relatively laborious to individually check each the control panel of each patient monitor in a health care facility to determine whether or not the alarm has been so lowered, and this is especially true in low light conditions. That is, in order to determine the alarm volume of a conventional patient monitor the parameter panel (which might be located, for example, on the front or top of the unit) must be consulted which means a trip across the room, application of illumination to the panel (if it is dark), and, possibly, selection of the appropriate alarm volume parameter from among several parameters in a multi-function display.
Heretofore, as is well known in the patient monitor arts, there has been a need for an invention to address and solve the above-described problems and, more particularly, there has been a need for an electronic patient monitor that has an illuminated control panel for use in low-light conditions. Additionally, there has been a further need for a way to easily determine whether or not a patient monitor has been set into low-volume mode, and this is especially true when that determination needs to be made in low-light conditions. Accordingly, it should now be recognized, as was recognized by the present inventors, that there exists, and has existed for some time, a very real need for a system for monitoring patients that would address and solve the above-described problems.
Before proceeding to a description of the present invention, however, it should be noted and remembered that the description of the invention which follows, together with the accompanying drawings, should not be construed as limiting the invention to the examples (or preferred embodiments) shown and described. This is so because those skilled in the art to which the invention pertains will be able to devise other forms of this invention within the ambit of the appended claims.